Method of extrusion and apparatus therefor



c. o. EVANS Iii T1101) OF EXIRUSION AND APPARATUS THEREFOR Sept. 29,1931;

' Filed March 5, 195::

'5 Sh qts-Sheet 1 -INVEN R KQ ATTORN EYS Z c. o. E-VANS .Sept. 29, 1931.

METHOD OF EXTRUSION AND APPARATUS THEREFOR Filed March 5. 1950 5Sheets-Sheet. 2

5 Sheetsi-Sheet 3 C. O. EVANS METHOD or EXTRUSION- ANpAPPARATus muttonFiled March 5. 1930 F'I Gr. 6.

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w s m Sept. 29, 1931.

E ATTORiEYS Z Sept. 29, 1931.

c. o. EVANS 1,825,343 METHOD OF EXTRUSION AND APPARATUS THEREFOR FiledMarch 5. 93:: s Sheets-Sheet 4 Fl GL9. 2:

1/ l l'" l INVENT OR.

Sept. 29,1931. I c. o. EVANS- v 1,825,343

METHOD EXTRUSION AND APPARATUS THEREFOR Filed March 5. 1950 s Sheets-Sheet 5 V 5 FIG. 10.

VENTZR BY Patented Se t. 29, 1931 UNITED STATES PATENT orricaIpplication filed March 5, 1930. Serial No. 433,228.

This invention relates to the art of extrusion, and to the apparatustherefor, and has particular reference to the extrusion of metal tubing,with a view mainly to uniformity of thickness of the walls of the tubethroughout its longitudinal and circumferential extent.-

The extrusion of tubing has under a certain practice been effected byforcing the metal, held in a container, through an extrusion die andaround a mandrel extending within the container and into the die, and ithas been attempted in this practice to center the mandrel in relation tothe die by forming a central bore in the billet or metal charge beforeintroducing the same into the container, and projecting the mandrel intosaid bore. This procedure has not proved entirely satisfactory, becausein order to slide a hot billet into the cylindrical chamber of thecontainer, a substantial clearance is demanded between the billet andchamber walls (in other words, the billet must be less in diameter thanthat of the chamber), and hence the center line of the containerand thecenter line of the billet will vary to an extent corresponding to theSince it is necessary to amount of clearance.

ush the mandrel through the bore in the illet before exerting theextrusion pressure, it follows that when this pressure is applied,

the billet (being shortened in taking up the clearance, and its diameterbeing increased) will be caused to completely fill the container, withthe result that the center line of the billet, and consequently that ofthe mandrel will be displaced relative to the center of the die, and themandrel will be forced out of the true line of extrusion. The extrudingaction under these conditions will result in the formation of a tubehaving an eccentric bore and with the walls consequently off gauge.

The present invention -overcomes these obj'ections by casting the billetdirectly into the container, while at the same time forming in thebillet a mandrel centering bore. This operation is preferably effectedby pouring the molten metal charge into the container while held in anupright position and around a removable bore formlng core therein, whichcore on being removed from the metal charge,

after the latter has more or less solidified in the form of a billet,bore therein.

Under this procedure, the metal charge will completely and solidly fillthe container, andthe bore in said charge will be in the true line ofthe center of the container, so that when the mandrel is inserted insaid bore, it will extend in the true extrusion line and will be willleave a. centering accurately centered in relation to the die.

Consequently, a uniform annular extrusion no space will exist betweenthe exterior of the mandrel and the interior of the die, and the tubingextruded through said s ace will have a truly concentric bore and wallsof uniform thickness throughout their longitudinal and 05circumferential extent.

In carrying out this procedure, an apparatus is employed of novel formand construction, wherein two containers are adapted to be supportedalternately in operative relation to the extrusion die, said containersbeing movable from their operative positions laterally to points freeof'the die for the purpose of recharging, one of the containers be ingrecharged while the metal is being extruded from the other container andvice versa, whereby the extruding operations will be carried oncontinuously and without waste of time.

As a further novel characteristic of the an apparatus, a cradleis'employed at the end of a guideway leading laterally from the point ofoperative support of a container, into which cradle the container ismoved in a horizontal' position from the guideway, and by which it isadapted to be turned to an up right charge-receiving position; and forthe formation of the mandrel centering bore in the charge or billet, ashereinbefore referred to, ajcore is mounted movably on the cradle, andby suitable means is thrust into the container, so that the billet maybe cast therearound, and is then removed fromthe billet to leave a boretherein.

These and other features of operation and construction of the inventionwill be described in detail in the specification to follow, and thenovel characteristics thereof will be pointed out in the appendedclaims.

In the accompanying drawings- Fig. 1 is a plan view, partly in section,of

the main portion of an extrusion press suitable for practicing theinvention;

Fig. 2 is a sectional elevation of thesame;

Fig. 3 is a vertical sectional elevation on an enlarged scale through anoperatively positioned container and the extrusion die, the sectionbeing taken on the line 3-3 of Figs. 1 and 2;

Fig. 4 is a transverse sectional elevation of the same on the line 44.-of Fi 3;

Fig. 5 is a rear elevation 0 one pf the cradles for turning thecontainer to an upright position for recharging, the same being shown ina position to receive the empty container in horizontal position;

Fig. 6 is a side elevation of the same;

Fig. 7 is a sectional view of the cradle, with the container in thecradle, and the latter rocked from the positionshown in Fig. 6 through90 to turn the container to an up right charge receiving position;

Fig. 8 1s a view similar to Fig. 7, showing the container filled withthe metal charge or billet and with the core seated therein;

Fig. 9 is a view similar to Fig. 8, showing the cradle moved back to theposition shown in Fig. 6 and with the core withdrawn from the billet,and the charged container ready to be moved from the cradle and returnedto operative relation to the extrusion die;

Fig. 10 is a view showing in section the container with its cored billetand the extrusion die, and showing in elevation the mandrel and rambefore the mandrel is entered in the die;

Fig. 11 is a similar view showing the mandrel seated in the bore in thebillet and centered in the die;

Fig. 12 is a view similar to Fig. 11 and showing the ram acting at therear end of the billet and extruding the metal through the die in theform of a tube.

Referring to the drawings- The extrusion press illustrated and to whichthe invention is applied, comprises as usual an extrusion die 1, a ram2, an associated mandrel 3 movable relatively to the ram within alongitudinal guiding opening therein, and a container 4 for the metal tobe extruded, which container inaccordance with the invention is adaptedto be positioned in operative relation to the die, mandrel and ram, .andto be bodily removed therefrom for recharging, there being in thepresent form of the invention, two of these containers which arepositioned and recharged alternatlely, as will be presently described indetai The die, ram and mandrel are mounted as usual in a massiveframework, comprising a rear frame block 5, and a front frame block (notshown), which blocks are connected together and maintained in fixedspaced relations by fourheavy tie bars 5*.

Upper and lower guiding flanges 6 and 7 project forwardly from the frontface of the rear frame block, and are formed in their inner sides withguiding grooves 6 and 7, which flanges are adapted to receive betweenthem, and act as guides for,'the containers 4 in the positioning of thesame alternately in horizontal operative relation to the die, mandreland ram, the upper and lower sides of the containers being formed withflat faces to fit between the guiding flanges, and being furtherprovided with ribs 8 to enter the guiding grooves 6 and 7 a in saidflanges.

As best shown in Figs. 1 and 3, when the container is positioned betweenthe flanges and in operative relation to the die, etc., the die projectsa slight distance into the front end of the container, and in order toadmit of the movement of the container into and out of operativeposition, the die is adapted to be moved forwardly to a limited extentaxially of the container in order to clear the rear end of the latter;and in the operative position of the parts as shown in these figures,the central horizontal longitudinal axes of the die, the container, theram and the mandrel, are coincident with each other and disposed in thetrue line of extrusion.

Horizontal guideways 9, 9, extend laterally in opposite directions fromthe respective ends of the lower guiding flanges 7, and formcontinuations of said flanges, and onto said guideways the containers-inhorizontal position are adapted to be moved when positioning them intooperative relation to the die for the extrusion operation, and inremoving them from the die for recharging; and supporting devices, inthe form of cradles 10, are arranged at the ends of said laterallyextending guideways to receive the respective containers from saidguideways, which cradles are adapted to be rocked to turn the containerssupported therein to upright charge-receiving positions.

As the two cradles are identical in construction and operation, beingduplicated on opposite sides of the .press to handle two con tainersalternately, a detailed description of one will suflice. As best shownin Fig. 6, the cradle consists of a frame provided with upper and lowerguiding flanges 11 and 12 having grooves 11 and 12 therein, similar tothe grooved flanges 6 and 7 of the rear frame block 5; and with thecradle in horizontal receiving position, the lower horizontal flange 12thereon will be in register with and form a continuation of the laterallextending guideway 9, so that the contalner may be moved directly intothe cradle from the guideway and will fit in between the flanges of thecradle, with the ribs of the container seated in the grooves in saidflanges.

The flanged frame of the cradle is rotatably mounted on a suitable fixedbed frame 13 in such a manner that the cradle frame may be turnedthrough 90 from its horizontal receiving position, to a verticalposition as shown in Fi 7, thereby to turn the container to an u rig tposition to receive its molten 5 metal c arge. This mounting of thecradle frame is efi'ected, in the present instance, by fixing to thesaid frame at its opposite sides, two segmental racks 14 which mesh withand are supported by two airs of vertical pinions 15 journalled in theed frame 13, whereby the cradle is rotatably sustained by said pinionsand may be rocked, either manually or by power, through 90 in turningthe container to an upright position for recharging, and in returningthe container to a horizontal position preparatoryto again moving thesame along the horizontal guideway 9 in again positioning the containerfor the extrusion operation. The container may be moved along theguideway 9 and into the cradle in any suitable manner, but as apreferred means for this purpose, a power cylinder 16 is fixed on asuitable support at the outer side of the cradle and containsa piston 17having connected .With it a piston rod 18 which extends between theflanges of the cradle frame and has its inner end pivotally connectedwith the side o f -the container as at 18 as best shown in Figs. 1 and2. 'By the admission of fluid under pressure to the cylinderrespectively on opposite sides of the piston (which may be accomplishedby controlling valve mechanism well known in the arts and not necessaryhere to illustrate), the piston may be stroked outwardly and the emptycontainer thereby moved from its operative position onto the cradle, orthe piston may be stroked inwardly and the container, after l0 receivingits new charge, may be moved out of the cradle and back to operativeposition for the next extruding operation, the turning of the containerto upright position within the cradle, notwithstanding the conl6 nectionof the latter with the piston rod, be-

ing permitted bythe turning movement of the piston within its cylinder.

When the empty container held in the cradle is turned to uprightposition as shown 0 in Fig. 7 molten metal is poured into the same, forinstance from a suitable ladle 19 to recharge the container; and inaccordance with the present invention and as before explained, a mandrelcentering bore A is formed 5 1n the charge or billet B, by inserting abore forming core 20 into the empty container before the molten metal isintroduced, and withdrawingsaid core after the charge has more or lesssolidified; This core as shown 0 in Figs. 6, 7 and 8 is of taperingform, so that it may be the more readily withdrawn from the coolingmetal mass, and it is mounted to slide back and forth through a guidinghole 21 inthe side of the cradle frame, which 5 hole, when the containeris positioned inthe cradle, will be in alinement with the longitudinalcenter of the container. At its outer end, the core is connected with acrosshead 22, which is connected with the forward ends of actuatingpiston rods 23 connected in turn with pistons 24 in tpower cylinders 25fixed to the outer sides 0 the flanges 11 and 12 of the cradle frame. Bythe admissionof pressure fluid to the cylinders respectively on o positesides of the pistons (which may be e ected by suitable valve mechanismsnot necessary to here illustrate, since they are well known in the art),the pistons may be stroked inwardly to project the core into thecontainer held in the cradle, or they may be stroked outwardl towithdraw the'core from the charge or bil et.

As shown in Fig. 8, the length of the core 20 is such that when fullyseated in the container, its free end will project a short distancebeyond the open end of the container, so as to insure that the metalcharge will not cover the end of the core and thereby close the end ofthe bore therein.

As shown also in Fig. 8, a closely fitting follower block 26 is seatedin the bottom of the container before the molten metal is poured in, andis rovided with a central hole through which t e core slides, thepurpose of which is to afford an abutment surface for the ram inexerting its extrusion pressure on the billet, whereby the ram without aclose fit in the container is enabled to exert its full pressurethroughout the cross sectional area of the billet.

It will be understood from the foregoing description, that the twocontainers are'operated alternately in positioning the charged containerfor its extrusion operation, and in removing the empty container fromthe extrusion position to its cradle for recharging, the empty containerbeing recharged while the billet is being extruded from the othercontainer. This method of operation conserves much time, and increasesthe capacity of production, and is' therefore a feature of im ortanceand advantage.

he operation of the mechanism in the practice of the invention is asfollows: It is assumed that the billet has been extruded from thecontainer shown in Fig. 1, thereby leaving the container empty, and thatthe ram and mandrel have been retracted for the next extrudingoperation. The extrusion die is first moved rearwardly to disengage thecontainer, and the latter is shifted along its guideway 9 in horizontalposition by the op eration of its piston 17, and entered in the cradlewhich was previously set in a receiving position with itsbore formingcore retracte'd. The container being thus seated in horizontal positionin the cradle, it-is fastened in place by suitable means 'to prevent itsdisplacement, and the bore forming core is stroked inwardly by theoperation of its pis' tons 24 and thus positioned in the center of thecontainer, it bein understood that previous to the seating o the core,or before the metal change is introduced the follower block 26 is placedin the bottom of the container as hereinbefore described. The cradle isnow rocked 90 from its horizontal receiving position, thereby turningthe container to upri ht charge receiving position as shown in F ig? 7Molten metal is now poured into the container so as to fill the samejust short of the end of the core, as shown in Fig. 8, and when thecharge has partially solidified into the billet B, the cradle is rockedback to its former horizontal position, and the core then strokedoutwardly and withdrawn from the billet, as shown in Fig. 9, therebyleaving in the billet the mandrel centering bore A, before alluded to.The charged container is now moved in horizontal position out of thecradle and along the guideway 9 by the operation of its piston 17 andpositioned in line with the die and mandrel, as shown in Fig. 10, readyfor the extrusion operation, and the die is engaged in the forward endof the container and abutted against the end of the billet. The mandrel3 is now advanced through the follower block 26 and the bore in thebillet, and its end entered in the die as shown in Fig. 11, theengagement of the mandrel in the bore of the billet (which bore isaccurately centered, due to the casting of the billet directly in thecontainer and around the core), acting to center the mandrel withextreme accuracy within the opening in the die. In this way, there isformed between the exterior of the mandrel and interior of the die, anannular extrusion space C of equal and uniform width throughout itscircumferential extent, as shown in Fig. 11. Finally the ram 2 isadvanced, and engaging and pushing the follower block before. it, thebillet is subjected to extrusion pressure and the metal is extrudedthrou h the extrusion space 0 in the form of tubingi), whose bore istruly concentric and whose walls are of uniform and equal thicknessthroughout its longitudinal and circumferential extent.

After all of the metal has thus been extruded, the ram and mandrel areretracted, and the die moved forwardly to disengage the container, andthe latter is again moved along the guideway 9 and into the cradle andrecharged, as above described, during which recharging operation theother container (which had been charged during the extrusion operationjust described) is moved into operative relation to the die, etc., andthe metal extruded therefrom as in the previous operation. 7

The container when in extrusion position is held by suitable meansagainst accidental displacement, in the present instance by means of avertically movable latch pin 27 mounted in a guideway inthe upper flange6 of the frame block 5, the lower end of said pin being rounded to seatin a rounded cavity in the upper side of the container. The relation ofthe cavity to the central axis of the container and the true line ofextrusion is such that when the pin is engaged in the cavity, the axisof the container will be in alinement with said line of extrusion, andconsequently in line with the axes of the die, ram and mandrel. Thelatch pin is controlled by fluid pressure means by being connected witha piston 28 in a cylinder 29 supplied with fluid under pressure from asuitable source through pipes 30 and 31 entering said cylinderrespectively on opposite sides of the piston. By means of suitable valvemechanism not necessary to illustrate or describe, the pressure on thelatch pin may be so controlled as to hold the same firmly engaged withthe container while the extrusion operation is in progress, and topermit the container to be automatically engaged with or disengaged fromthe latch pin in positioning the container for the extrusion operationand in removing the empty container therefrom, the rounded end of thepin admitting of such automatic action.

While in the foregoing description and accompanying drawings theinvention has been set forth in the particular detailed form and methodof procedure which have been found to answer to a satisfactory degreethe ends to be attained, it will be manifest that these details may bevariously changed and modified without departing from the spirit of theinvention; and it will be understood that the invention is not limitedto any particular form or construction of parts, or in respect .to themethod of procedure, except in so far as such limitations are specifiedin the claims.

Having thus described my invention, what I claim is 1. The method ofextruding tubing, which consists in casting in a container a heatedbillet with a mandrel centering bore, supporting the container inoperative relation to an extrusion die, and a mandrel, inserting themandrel in the bore of the billet and thereby centering the mandrelrelative to the die, and acting on the billet to extrude the metalthrough the die and around the mandrel.

2. In the method of extruding tubing, introducing molten metal into acontainer around a bore forming core, permitting the metal to more orless solidify to form a billet, withdrawing the core from the billet toleave a mandrel centering bore therein, inserting a mandrel within themandrel centering bore to permit extrusion of the tubing.

3. In the method of extruding metal tubing, turning the container to anupright position while removed from the extrusion die, inserting a boreforming core into the container, filling the container around said corewith molten metal, permitting the molten the extrusion die, inserting amandrel into Core metal to partially solidfy, withdrawing the leave amandrel centering bore said charge, moving the container in operativerelation to said bore in the metal charge, and subjecting the metal char.to pressure to extrude the same through t e die.

relation to the extrusion die,

-4. In the method of extrusion, turning the container to an uprightposition while removed from the extrusion die inserting a bore formingcore in the upright contamer, char the container with molten metal tosurroun the inserted core, dpermittin the molten metal to partially soli'fy, with rawing the core from the partially solidified char to leave amandrel centering bore, turning the charged container to a horizontalposition, and moving the same to operative inserting a mandrel in thecentering bore in the metal charge, and subjecting the charge topressure to extrude the same through the die.

5. The method of extrusion, which consists in employin two containersfor the material to be extruded, positioning. said containersalternately in operative relation to an extrusion die, removing theempty containers alternatel from the die to receive fresh charges 0container while material is being extruded from an operativelypositioned container.

6. The method of extrusion, which consists in employing two containersfor the material to be extruded, positioning said containers alternatelyin operative relation .to an extrusion die, removing the emptycontainers alternately in opposite dlrectlons from the die to positionsfor recharging, and charging an empt ing the material rom an operativelyPOSI- tioned containen, y

7 The method of extrusion, which consists in employing two, containersfor the ma terial to be extruded, positioning said containersalternately horlzontally in operative relation to an extrusion die,removing the empty container alternately from the die and turning themto an upright position to receive fresh charges of material, and pouringmolten metal in an upright empty container while the other container ishorizontally positioned in operative relation to the extrusion die. 7

8. In an extrusion'press, the combination of an extrusion die, acontainer adapted to be removably supported in horizontal position inoperative relation to the die, a reciprocating ram, means for movin theempty contalner transversely of the irection of movement of the ram to apoint removed from the die, and a supporting device in position toreceive the container, said device being movable to turn the containerto an upright position for from the partially solidified charge tomaterial, and charging an emptycontainer while extrud- 9. In anextrusion press, the combination of an extrusion die, anextruding ramreciprocatable to and from the die, a container for the material to beextruded, a support for the container between the ram and dle, aguideway extending laterally from the container support for t e movementof the container free of the die and ram, and a device at the end of theguideway to receive the container, said device being movable relative tothe guideway to turn the container to an upright position for charging.

10. In an extrusion press, the combination of an extrusion die, anextrusion ram reciprocatable to and from the die, a movable containerfor holding the material to be extruded, a support for the containerbetween the ram and die, a guideway extending laterally from'thesupport, a cradle at the end of said giudeway and power means operativeon the container to move it along said uideway and onto the cradle, saidcradle eing movable to turn the container to an upright charge-receivingposition.

11. In an extrusion press, the combination of an extrusion die,rocatable to and from the die, movable containers for the material to beextruded, a support for the containers to sustain themalternatelybetween the ram and die, guideways extending laterally inopposite directions from said support, means for moving the containersback and forth on said guideways to respectively position the chargedcontainers in operative relation to the die and ram, and to remove theempty containers for recharging, and means whereby said containers canbe turned to upright charge-receiving positions at the ends of theirlateral movements.

12. In an extrusion press, the combination of an extrusion die, anextrusion ram reciprocatable to and from the die, movable containers forthe material to be extruded, a support for the containers to sustainthem in horizontal position alternately between the ram and die,guideways extending laterally in opposite directions from said supporton which the containersare adapted to be moved, cradles at the ends ofthe guideways to receive the horizontal containers respectivelytherefrom, fluid pressure cylinders, and pistons therein connected withthe respective containers to move them alternately .along theirguideways and into said cradles in horizontal position, said cradlesbeing rockable to turn the containers to vertical position for rechargin13. In an extrusion press, the combination of an extrusion die, anextrusion ram reciprocatable to and from the die,movable contain ers forthe material to be extruded, a support for said containers between theram and die, guideways extending laterally from said support, on whichthe containers are adapted to be moved free of the ram and die, and

cradles at the ends of said guideways to receive the containers, saidcradles being movable to turn the containers to upright chargereceivingpositions.

14. In an extrusion press, the combination of an extrusion die, anextrusion ram reciprocatable to and from the die, a container for thematerial to be extruded, a support for the container between the ram anddie, a guideway extending laterally from the container support for themovement of the container free of the die and ram, a cradle at the endof the guideway to receive the container and movable to turn thecontainer to an upright charge-receiving position, and a core carried bythe cradle and adapted to be inserted in the container to form acentering bore in the metal charge.

15. In an extrusion press. the combination of an extrusion die, anextrusion ram, a mandrel associated with said ram, a container for thematerial to be extruded, a support for the container between the ram anddie, a guideway extending laterally from the container support for themovement of the container free of the ram and die, a cradle at the endof said guideway in position to receive the container, said cradle beingrockable to turn the container to an upright charge-receiving position,means for moving the container along said guideway and onto the cradle,a core on the cradle adapted to be inserted in the container while inthe cradle and to be removed from the metal charge therein to leave amandrel centering bore, and means for operating said core.

16. In an extrusion press, the combination of an extrusion die, acontainer adapted to be supported in operative relation to the die andremovable therefrom for recharging, a device in position to receive theremoved container and movable to support the same in an upright positionto receive the charge of molten metal, a core mounted on said device,and means for operating the core to respectively insert it in and removeit from the supported container, thereby to form a centering bore in themolten metal.

17. In an extrusion press, the combination of an extrusion die, acontainer adapted to be supported in operative relation to the die andremovable therefrom for recharging, a device in position to receive theremoved container and movable to support the same in an upright positionto receive the molten metal, a core movably mounted on said device forinsertion in and removal from the supported container, and fluidpressure operating means on said device for actuating the core.

18. In an extrusion press, the combination of an extrusion die, acontainer adapted to be supported in operative relation to the die andremovable therefrom for recharging, a device in position to receive theremoved container and movable to support the same in an upright positionto receive the molten charge, a core movably mounted on said device, afluid pressure cylinder and piston therein, and connections between thepiston and corefor operating the latter.

- 19. In an extrusion press, the combination of an extrusion die, acontainer adapted to be supported in operative relation to the die andremovable therefrom for recharging, a device in position to receive theremoved container and movable to support the same in an upright positionto receive the molten charge, a core movably mounted on said device forinsertion in and removal from the supported container, fluid pressurecylinders fixed to said device, pistons sliding therein, and a crossheadcarried by the core and connected to said pistons to be operatedthereby.

20. In an extrusion press, the combination of an extrusion die, acontainer for the material to be extruded, a support by which thecontainer is held removably in operative relation to the die, a guidewayextending laterally from said support on which the container is adaptedto be removed from the die, a pressure fluid cylinder, a piston thereinconnected with the container for moving it along the guideway, and acradle formin a continuation of said guideway to recelve the containertherefrom, and rockable to turn the container to an upright position forrecharging.

21. In an extrusion press, the combination of an extrusion die, acontainer for the material to be extruded, a support by which thecontainer is held removably in operative relation to the die, a guidewayextending laterally from said support on which the cradle is adapted tobe moved free of the die for recharging, a cradle at the end of saidguideway formed with upper and lower guides to receive the containerfrom the laterally extending uideway, and means for moving the containeralong the laterally extending guideway and into the ides of the cradle,said cradle being rockab e to turn the container to an upright positionfor recharging.

22. In an extrusion press, the combination of an extrusion die, acontainer for the material to be extruded, upper and lower guidewaysbetween which the container is adapted to be removably supported inoperative relation to the die, a horizontal guideway extending laterallyfrom said lower guideway on which the container is adapted to be movedfree of said die, a cradle at the end of said lateral guideway providedwith upper and lower guideways between which the container is receivedfrom the lateral guideway, said cradle being rockable to turn thecontainer to an upright position for recharging, and means for movingthe container along the lateral guideway and into the guideways' on thecradle. V 23. In an extrusion press, the combination of an extrusiondie, a container tohold the material to be extruded, a uideway on whichthe container is adapte to be supported in operative relation to thedie, and releasable means acting on the container to hold it removablyin said operative relation. 24. In an extrusion press, the combinationof an extrusion die, a containerfto hold the material to be extruded, aguideway on which the container is adapted to 'be suported in operativerelation to the die, means or moving the container on said guideway intoand out of operative relation to said die, and a latch pin adapted to beinterlocked with the container to hold it in osition, and beingyieldable to permit 0 its automatic engagement and disengagement by themovement of the container.

25. In an extrusion press, the combination of an extrusion die, acontainer to hold the material to be extruded and-provided with acavity, means for supporting the container in operative relation to theie, a latch pin adapted when the container is in said osition to engagein said cavity and hol the container removably in position, a fluidpressure cylinder, and a piston therein connected with said pin.

In testimony whereof, this specification has been duly signed by:

CLAIR O. EVANS.

